| Moving and Accessing SAS Files across Operating Environments |
To avoid
potential problems when transferring
a transport file to the target host, ensure that these conditions have been
met.
- If transferring across the network, verify that
the transport file is transferred in binary format. See Transferring the Transport File in Binary Format for more information.
- Verify
that the transport file has not been corrupted.
See Verifying That the Transport File Has Not Been Corrupted
for more information.
- Verify that the communications software does not
change file attributes. See Verifying That the Communications Software Has Not Changed File Attributes
for more information.
- Consider invoking the communications software
at the target host and getting the transport file from the source host. See Invoking the Communications Software at the Target Host for more
information.
- Do not mix methods to create the transport file
at the source host and then to restore the transport file at the target host.
See Using Compatible Transport Methods at the Source and Target Hosts
for more information.
- Before you transfer a transport file to the target
host, validate the integrity of the transport file by restoring it to the
source host that created it. See Validating the Integrity of the Transport File
for more information.
- If transferring by means of tape, use an unlabeled
tape. See Using an Unlabeled Tape
for more information.
- If transferring a large transport file by means
of tape, break up the library into multiple libraries and transport each one
to tape. See Dividing a Large Transport File Into Smaller Files for Tape
for more information.
Remaining sections explain these topics in detail.
When transferring a transport file using
the communications software, verify that the file is transferred in binary
(or image) format. The content of the file must be transferred in sequential
bytes without modification.
If you use FTP to move a transport file to the target
host, you should first specify BINARY 80 before transferring the file.
If you use PATHWORKS, use the SEQUENTIAL_FIXED attribute
when you set the file_server service using PCSA_MANAGER. The default attribute
is STREAM, which is not appropriate for moving transport files.
Verify that your communications
software does not insert a carriage return to mark an end of record in the
transport file during transfer to the target host. The insertion of carriage
returns and line feeds corrupts the transport file, making it impossible to
restore at the target host. For details about how to determine this condition,
see the recovery actions for File libref.ALL is damaged. I/O processing did not complete.
Verify that your communications
software does not change file attributes. Here are the required attributes
with values:
| Logical record length (LRECL) |
80 |
| Block size (BLKSIZE) |
8000 blocks |
| Record format (RECFM) |
Fixed block |
See your communications software
documentation for information
about controlling these attributes.
At the target host, if you have a transport file that
has not been corrupted (carriage returns or line feeds have not been inserted),
but whose record block size is incorrect and you are unable to obtain a correctly
blocked transport file, you may run a reblocking program to fix the blocks
to the correct size. For details, see Reblocking a Transport File.
To transfer the transport
file to the target host, you may be
more successful invoking the communications software at the target host than
at the source host. You probably cannot put a file in a location on the target
host because you do not have write permission. For example, if transferring
a transport file from UNIX to CMS, you are advised to invoke the communications
software at the CMS host. Because you probably have read permission at the
UNIX host, you can get the transport file and write it to your CMS host.
Do not mix methods to create the transport
file at the source host and then restore the transport file at the target
host. The methods that you use must be identical or be a companion pair. For
example, create and restore a transport file using the XPORT engine and PROC
COPY at both the source and target hosts. Likewise, create a transport file
using PROC CPORT at the source host and import the transport file using PROC
CIMPORT at the target host. Do not, for example, create a transport
file using the XPORT engine and PROC COPY at the source host and then try
to use PROC CIMPORT to restore the
transport file at the target host.
To determine the method that was used to create a transport file, use a text
editor or an operating system read or view command to read the file on any
Version 8 host that represents character data as ASCII.
Note: For information about viewing transport files on hosts that represent character
data as EBCDIC, see Representing EBCDIC as ASCII or Hexadecimal Data. ![[cautionend]](../common/images/cautend.gif)
The XPORT engine creates a file whose first line contains this
ASCII text:
HEADER RECORD*******LIBRARY HEADER RECORD!!!!!!!00
PROC CPORT creates a file whose first line contains
this text:
**COMPRESSED** **COMPRESSED** **COMPRESSED**
Note: If you set the NOCOMPRESS option to PROC
CPORT, compression is suppressed, which prevents the display of the preceding
text in a transport file.
To validate the integrity of
the transport file before it is transferred to the target host, using the
appropriate method, try to read it back into native format at the source host.
Here is a PROC COPY example:
/* This PROC COPY creates the transport file TRAN. */
libname tran xport 'transport-file';
libname grades 'SAS-data-library';
proc copy in=grades out=tran memtype=data;
run;
/* This PROC COPY reads back transport file TRAN. */
libname grades 'SAS-data-library';
libname tran xport 'transport-file';
proc copy in=tran out=test;
run;
Here is a PROC CPORT and PROC CIMPORT example:
/* This PROC CPORT creates the transport file. */
libname grades 'SAS-data-library';
filename tran 'transport-file';
proc cport library=grades file=tran;
run;
/* This PROC CIMPORT reads back the transport file. */
filename tran 'transport-file';
libname grades 'SAS-data-library';
proc cimport library=grades infile=tran;
run;
For both examples, check the log for error messages.
When transferring a transport file by means of
tape, use an
unlabeled tape. Because tape labels are processed differently in different
operating environments, reading a file from a standard label tape may be somewhat
complicated at the target host.
When transferring a transport file
by means of tape, if the transport file exceeds the capacity of one tape,
rather than using multi-volume tapes, you should divide the original library
into two or more libraries and create a separate, unlabeled tape for each
one. The original library can be restored at the target host.
Copyright 1999 by SAS Institute Inc., Cary, NC, USA. All rights reserved.
